diff --git a/tests/e2e/test_mars_lvig.py b/tests/e2e/test_mars_lvig.py
new file mode 100644
index 0000000..8cd7868
--- /dev/null
+++ b/tests/e2e/test_mars_lvig.py
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+"""MARS-LVIG stress tier — featureless sequences, completion-rate gate."""
+
+from pathlib import Path
+
+import pytest
+
+from gps_denied.testing.datasets.mars_lvig import MARSLVIGAdapter
+from gps_denied.testing.harness import E2EHarness
+
+
+# Stress tier does not gate on RMSE — featureless sequences legitimately cause
+# tracking loss. The gate is whether the pipeline RUNS TO COMPLETION without
+# crashing, and what fraction of frames produced any estimate at all.
+MARS_COMPLETION_FLOOR = 0.0  # initial: any run-to-completion passes; tighten later
+
+
+@pytest.mark.e2e
+@pytest.mark.e2e_slow
+@pytest.mark.needs_dataset
+@pytest.mark.asyncio
+async def test_mars_lvig_runs_to_completion(mars_lvig_root: Path):
+    # Pick the first available sequence under mars_lvig_root
+    seqs = sorted(p for p in mars_lvig_root.iterdir() if p.is_dir())
+    if not seqs:
+        pytest.skip(f"No MARS-LVIG sequences found under {mars_lvig_root}")
+    adapter = MARSLVIGAdapter(seqs[0])
+    harness = E2EHarness(adapter)
+    result = await harness.run()
+    assert result.num_frames_submitted > 0
+    completion_rate = (
+        result.num_estimates / result.num_frames_submitted
+        if result.num_frames_submitted else 0.0
+    )
+    assert completion_rate >= MARS_COMPLETION_FLOOR, (
+        f"Completion rate too low: {completion_rate:.2%}"
+    )